The invention relates to an internal combustion engine comprising an intake channel for supplying fuel and combustion air, wherein a section of the intake channel is formed in a carburetor and wherein at least one fuel opening opens into the intake channel within the carburetor. The intake channel is connected by means of an intake opening to the clean chamber of an air filter from where the internal combustion engine takes in air through at least one filter element. A choke element is arranged in the clean chamber and can be moved into a choke position and into an open position.
U.S. 2001/0018898 discloses an internal combustion engine having an intake channel that can be closed off by a choke element arranged in an air filter. In the open state of the choke element, the choke element has been pivoted out of the area of the intake opening that opens into the intake channel. The pivot movement is carried out in the plane of the air filter bottom about an axis that is parallel to the longitudinal axis of the intake channel.
In internal combustion engines of this type, it can happen, as a result of the pulsations occurring during operation within the intake channel, that the fuel/air mixture flows back from the intake channel into the air filter. The fuel that flows from the intake channel into the air filter can cause soiling of the air filter element and thus can cause impairment of the intake action. In order to prevent soiling of the air filter, U.S. 2002/0135083 discloses the arrangement of a baffle wall in the air filter in the area of the intake opening of the intake channel.